7,909 research outputs found
Pedometers to enhance physical activity in COPD: a randomised controlled trial
Physical inactivity is a cardinal feature of chronic obstructive pulmonary disease (COPD), and is associated with increased morbidity and mortality. Pedometers, which have been used in healthy populations, might also increase physical activity in patients with COPD. COPD patients taking part in a 3-month individualised programme to promote an increase in their daily physical activity were randomised to either a standard programme of physical activity encouragement alone, or a pedometer-based programme. Assessments were performed by investigators blinded to treatment allocation. Change in average 1-week daily step count, 6-min walking distance (6MWD), modified Medical Research Council scale, St George’s respiratory questionnaire (SGRQ) and COPD assessment test (CAT) were compared between groups. 102 patients were recruited, of whom 97 completed the programme (pedometer group: n=50; control group: n=47); 60.8% were male with a mean±sd age of 68.7±8.5 years, and forced expiratory volume in 1 s (FEV1) 66.1±19.4% and FEV1/forced vital capacity 55.2±9.5%. Both groups had comparable characteristics at baseline. The pedometer group had significantly greater improvements in: physical activity 3080±3254 steps·day−1 versus 138.3±1950 steps·day−1 (p<0.001); SGRQ −8.8±12.2 versus −3.8±10.9 (p=0.01); CAT score −3.5±5.5 versus −0.6±6.6 (p=0.001); and 6MWD 12.4±34.6 versus −0.7±24.4 m (p=0.02) than patients receiving activity encouragement only. A simple physical activity enhancement programme using pedometers can effectively improve physical activity level and quality of life in COPD patients
Effects of Social Identity, Self-Esteem, Schooling, and Age on Hope [Efectos de la Identidad Social, la autoestima, la Escolaridad y la Edad sobre la esperanza]
AbstractThe primary objective of this study was to analyze the direct explanatory power of social identity, schooling, and age on self-esteem, as well as the indirect effects of those variables (through the mediating variable self-esteem) on hope. A non-probabilistic sample composed of 657 persons from southern Nuevo Leon was recruited (mean age = 39.75 years; SD = 16.96). Structural equation modeling was used to analyze the effects, both direct and indirect, of the independent variables upon the dependent variables. With regard to hope, the model yields an explained variance of 37% (d ≥ 26% = large effect size) and shows well goodness-of-fit indices: χ2 / df = 2.618, GFI = .997, AFGI = .978, CFI = .995, NNFI = .995, NFI = .992, RMSEA = .048 (IC90%, .001, .100), and SRMR = .017. It is concluded that social identity, together with some contextual variables of a personal nature (for instance, age and schooling) is probably very important to explain the levels of self-esteem and hopeResumenEl objetivo primario de este estudio fue analizar el poder explicativo de las variables identidad social, escolaridad y edad, directamente sobre la autoestima y los efectos indirectos de las tres primeras, a través de la autoestima, sobre la esperanza. Se realizó el estudio en una muestra no probabilística de 657 hombres y mujeres, con edad promedio de 39.75 años (DE = 16.96). Se usó modelamiento de ecuaciones estructurales para analizar los efectos, tanto directos como indirectos, de las variables independientes sobre las dependientes. Se encuentra que el modelo tiene una varianza explicada del 37% (d = ≥ 26% = tamaño del efecto grande) en esperanza, con buenos indicadores de bondad de ajuste: χ2/gl = 2.618; GFI = .997; AFGI = .978; CFI = .995; NNFI = .995; NFI = .992; RMSEA = .048 (IC90%, .000, .100), SRMR = .017. Se concluye que probablemente la identidad social, junto con algunas variables contextuales de tipo personal, como la edad y la escolaridad, es prioritaria para explicar la existencia de la autoestima y de la esperanza
Energy System Planning towards Renewable Power System: Energy Matrix Change in Cuba by 2030
Since 2013, the biggest Caribbean island, Cuba, has been undertaking an energy matrix change. There is a strong political intention to replace fossil fuels by renewable energy and improve efficiency and security of the national energy system. By 2030, 24% of electric power shall be produced from renewable sources. Transition from centralized fossil fuel fired power system towards distributed renewable generation based system requires changes to conventional energy planning and system design procedures as well as physical structures of the national energy system. This paper introduces three analysis axis: Scenario building for future supply-demand balance, scenario for a 100% renewable energy system for Cuba, and a roadmap from existing power system to the system with high share of distributed renewable generation. This work is a part of European Union funded Erasmus+ project "Capacity Building for Renewable Energy Planning in Cuban Higher Education Institutions", CRECE.<br /
Proyecto IRESUD: interconexión de sistemas fotovoltaicos a la red eléctrica en ambientes urbanos. estado de avance a julio de 2014 y primeras mediciones en sistemas piloto
En el marco de una convocatoria del Ministerio de Ciencia, Tecnología e Innovación Productiva, se conformó, en el año 2011, el consorcio público-privado IRESUD entre la Comisión Nacional de Energía Atómica (CNEA), la Universidad Nacional de San Martín (UNSAM) y 5 empresas privadas, para la ejecución del proyecto “Interconexión de Sistemas Fotovoltaicos a la Red Eléctrica en Ambientes Urbanos”. El principal objetivo del mismo es introducir en el país tecnologías asociadas con la interconexión a la red eléctrica, en áreas urbanas, de sistemas fotovoltaicos (FV), contemplando para ello cuestiones técnicas, económicas y regulatorias. En este trabajo, se presenta el grado de avance del proyecto en lo referente a las cuestiones regulatorias y a las instalaciones piloto realizadas o en ejecución en diferentes partes del país. Asimismo, se muestran las primeras mediciones de algunas de las instalaciones actualmente en operación y se analiza el comportamiento de un inversor FV de conexión a red.Fil: Durán, J. C.. Comisión Nacional de Energía Atómica; Argentina. Universidad Nacional de San Martín; ArgentinaFil: Socolovsky, Hernan Pablo. Comisión Nacional de Energía Atómica; Argentina. Universidad Nacional de San Martín; ArgentinaFil: Raggio, D.. Comisión Nacional de Energía Atómica; ArgentinaFil: Godfrin, Elena María. Comisión Nacional de Energía Atómica; ArgentinaFil: Jakimczyk, J.. Universidad Tecnológica Nacional; ArgentinaFil: Martinez Bogado, Mónica Gladys. Universidad Nacional de San Martín; Argentina. Comisión Nacional de Energía Atómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Diaz, F. J.. Universidad Nacional de La Plata. Facultad de Informática; ArgentinaFil: Castro, N. E.. Universidad Nacional de La Plata. Facultad de Informática; ArgentinaFil: Pedro, G.. Provincia del Neuquen. Ministerio de Hacienda Obras y Servivcios Publicos. Ente Provincial de Energia del Neuquen; ArgentinaFil: Sepúlveda, O.. Provincia del Neuquen. Ministerio de Hacienda Obras y Servivcios Publicos. Ente Provincial de Energia del Neuquen; ArgentinaFil: Argañaraz, C.. Provincia del Neuquen. Ministerio de Hacienda Obras y Servivcios Publicos. Ente Provincial de Energia del Neuquen; ArgentinaFil: Benítez, E.. Universidad Nacional de Luján; ArgentinaFil: Roldán, A.. Universidad Nacional de Luján; ArgentinaFil: Righini, R.. Universidad Nacional de Luján; Argentin
Dirac Equation with Spin Symmetry for the Modified P\"oschl-Teller Potential in -dimensions
We present solutions of the Dirac equation with spin symmetry for vector and
scalar modified P\"oschl-Teller potential within framework of an approximation
of the centrifugal term. The relativistic energy spectrum is obtained using the
Nikiforov-Uvarov method and the two-component spinor wavefunctions are obtain
are in terms of the Jacobi polynomials. It is found that there exist only
positive-energy states for bound states under spin symmetry, and the energy
levels increase with the dimension and the potential range parameter .Comment: 9 pages and 1tabl
Inclusive Dielectron Production in Ar+KCl Collisions at 1.76 AGeV studied with HADES
Results of the HADES measurement of inclusive dielectron production in Ar+KCl
collisions at a kinetic beam energy of 1.76 AGeV are presented. For the first
time, high mass resolution spectroscopy was performed. The invariant mass
spectrum of dielectrons is compared with predictions of UrQMD and HSD transport
codes.Comment: 4 pages, 3 figures - To appear in the conference proceedings for
Quark Matter 2009, March 30 - April 4, Knoxville, Tennesse
The Sensitivity of HAWC to High-Mass Dark Matter Annihilations
The High Altitude Water Cherenkov (HAWC) observatory is a wide field-of-view
detector sensitive to gamma rays of 100 GeV to a few hundred TeV. Located in
central Mexico at 19 degrees North latitude and 4100 m above sea level, HAWC
will observe gamma rays and cosmic rays with an array of water Cherenkov
detectors. The full HAWC array is scheduled to be operational in Spring 2015.
In this paper, we study the HAWC sensitivity to the gamma-ray signatures of
high-mass (multi- TeV) dark matter annihilation. The HAWC observatory will be
sensitive to diverse searches for dark matter annihilation, including
annihilation from extended dark matter sources, the diffuse gamma-ray emission
from dark matter annihilation, and gamma-ray emission from non-luminous dark
matter subhalos. Here we consider the HAWC sensitivity to a subset of these
sources, including dwarf galaxies, the M31 galaxy, the Virgo cluster, and the
Galactic center. We simulate the HAWC response to gamma rays from these sources
in several well-motivated dark matter annihilation channels. If no gamma-ray
excess is observed, we show the limits HAWC can place on the dark matter
cross-section from these sources. In particular, in the case of dark matter
annihilation into gauge bosons, HAWC will be able to detect a narrow range of
dark matter masses to cross-sections below thermal. HAWC should also be
sensitive to non-thermal cross-sections for masses up to nearly 1000 TeV. The
constraints placed by HAWC on the dark matter cross-section from known sources
should be competitive with current limits in the mass range where HAWC has
similar sensitivity. HAWC can additionally explore higher dark matter masses
than are currently constrained.Comment: 15 pages, 4 figures, version to be published in PR
Future perspectives at SIS-100 with HADES-at-FAIR
Currently, the HADES spectrometer undergoes un upgrade program to be prepared
for measurements at the upcoming SIS-100 synchrotron at FAIR. We describe the
current status of the HADES di-electron measurements at the SIS-18 and our
future plans for SIS-100.Comment: Invited contribution presented at the XLVII International Winter
Meeting on Nuclear Physics, Bormio (Italy), Jan. 26-30, 200
All-particle cosmic ray energy spectrum measured by the HAWC experiment from 10 to 500 TeV
We report on the measurement of the all-particle cosmic ray energy spectrum
with the High Altitude Water Cherenkov (HAWC) Observatory in the energy range
10 to 500 TeV. HAWC is a ground based air-shower array deployed on the slopes
of Volcan Sierra Negra in the state of Puebla, Mexico, and is sensitive to
gamma rays and cosmic rays at TeV energies. The data used in this work were
taken from 234 days between June 2016 to February 2017. The primary cosmic-ray
energy is determined with a maximum likelihood approach using the particle
density as a function of distance to the shower core. Introducing quality cuts
to isolate events with shower cores landing on the array, the reconstructed
energy distribution is unfolded iteratively. The measured all-particle spectrum
is consistent with a broken power law with an index of prior to
a break at ) TeV, followed by an index of . The
spectrum also respresents a single measurement that spans the energy range
between direct detection and ground based experiments. As a verification of the
detector response, the energy scale and angular resolution are validated by
observation of the cosmic ray Moon shadow's dependence on energy.Comment: 16 pages, 11 figures, 4 tables, submission to Physical Review
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